This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. The Kapoor Lab is working to develop a general inhibitor for kinesins-- one class of motor proteins in the cell. We have shown that some of her inhibitors bind to the kinesin Eg5 by observing the protein-inhibitor complex using native mass spectrometry readout.